Oil spill recovery system

ABSTRACT

A system for deploying a cover over an oil spill, to collect the spilled oil, uses a plurality of gas propelled rockets are attached to lines arranged around the periphery of the cover. Outward projection of the rockets spreads the cover, the weight of the expended rockets then pulling the edges of the cover below the water surface to trap the covered oil. Attitude detectors are preferably employed for preventing firing of the rockets when the rocket platform is not generally level.

This is a continuation of copending application(s) Ser. No. 07/991,313filed on Dec. 16, 1992 now U.S. Pat. No. 5,407,310.

The present invention is directed to oil spill recovery systems whichcan be rapidly deployed to confine and collect oil and other liquidsfloating on the surface of a body of water for subsequent disposal bysuitable recovery systems.

BACKGROUND OP THE INVENTION

In the recovery of oil spills, it is essential that recovery operationsbegin as soon as possible after the spill. For this purpose new U.S.Coast Guard regulations require that oil tankers have available adequatesystems for recovering all oil which could be released in the event of aspill. Such systems must be rapidly deployable and capable of operatingin a fool-proof and safe manner to capture the maximum amount of oilfloating on the surface of the water in the vicinity of the oil spill.

One proposed system for recovering spilled oil is described in U.S. Pat.No. 3,788,079 issued Jan. 29, 1974 to Kirk and Reynolds. This '079patent describes a system wherein a cover is deployed over an oil spillby spreading it horizontally over the spill. In this system weightsattached to lines connected to the periphery of the cover which is thetremendous fire hazard potentially created when a large explosive chargeis detonated in the vicinity of an oil spill. Another disadvantage isthe difficulty of assuring that all of the explosively propelled weightsare discharged outwardly at the same time with the same velocity toassure uniform deployment of the cover by the outwardly propelledweights.

BRIEF SUMMARY OF THE INVENTION

The present invention is directed to an improved deployment system for acover which is used to entrap floating oil. In a preferred form of theinvention, the cover is deployed by gas propelled rockets which use, asa motor force, high pressure gas confined by the rockets. Such a systemhas the advantage that no explosive flames are created to activate thesystem or to provide the propelling force. The rockets are independentlypropelled and can, themselves, act as weights necessary to draw theedges of the deployed cover below the surface of the water to entrap thecovered oil slick. Other novel features of the invention are the systemsfor holding the cover, venting the cover and storing the cover duringinitial deployment of the support carrying the cover with automaticrelease of the storage means as a result of the firing of coverdeployment rockets.

Additionally, the preferred form of the invention involves means forassuring that the cover deploying rockets are activated only when theyare in proper position to fully deploy the cover.

DETAILED DESCRIPTION OF THE INVENTION

In order that the invention may be more fully understood, referenceshould be had to the following detailed description taken in connectionwith the following drawings.

DETAILED DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagramatic side view of an inflated raft showing the coverbefore deployment held in a pocket with the firing tubes mounted abovean inflated tower.

FIG. 2 shows the raft immediately after firing of the rockets, showingthe initial stages of deployment of the cover.

FIG. 3 shows the raft with the cover deployed, the anchor released andoil entrapped.

FIGS. 4A and 4B show side and top views, respectively, of the inflatedraft with the inflatable platform.

FIG. 5 is a plan view showing the pockets for holding the cover, thepocket backing and the air vent for releasing air from under thedeployed cover. (For clarity, the cover is not shown)

FIG. 6 is a schematic partial sectional view showing a portion of theinflatable support, the vent, the pocket backing and a portion of thedeployed cover.

FIG. 7 is a side and top view of the rocket firing tube assembly.

FIG. 8 shows a schematic sectional view of the power supply, control andthe various sensors used for determining the proper time of firing.

FIG. 9 is a diagramatic view showing the arrangement of the bridleattached to the gas cylinder for deploying the cover when the gas rocketis activated.

FIG. 10 is a diagramatic schematic, partially cut away, drawing showingthe arrangement of the firing mechanism for rupturing the disk whichactivates the rocket.

FIG. 11 is a side view of the canister for holding the raft.

FIG. 12 is a schematic diagramatic partially sectional view of thedeflated raft and cover packed in the canister for storage, ready fordeployment.

FIG. 13 is a schematic diagramatic view of the initial stages ofinflation of the raft with the outer shell of the storage canister beingdiscarded.

FIG. 14 shows a schematic diagrammatic partial view of the inflated raftwith the cover deployed prior to releasing the anchor.

Referring now to FIGS. 1, 2 and 3, there is shown a diagramatic sideview of the present invention illustrating the raft, the cover and thefiring mechanism for deploying the cover.

In FIG. 1, the raft 10 is generally shown as an inflatable tubular ring11 having an inflatable tower 12 which has a plurality of legs whichsupport an inflatable upper platform 13. The rocket firing tubes 14 arecarried by the platform 13. Lines 22 connect each rocket to an outerperipheral portion of the deployable cover. In a preferred embodiment ofthe invention, there are eight gas rockets, each connected to one ofeight spaced points around the periphery of the cover. Only one of thedeploying lines 22 is illustrated, being schematically shown as leadingto the cover which is contained in the pocket 16.

In FIG. 2, the device is shown immediately after firing of all of therockets showing the cover 24 being pulled out of the pocket 16.

In FIG. 3, the cover has been fully deployed and has trapped a mass ofoil 100 under the deployed cover. As shown in this FIG. 3, an anchor 30has been released and is attached, by means of lines 32, to equallyspaced points around the perimeter of the cover. The anchor thus tendsto pull the periphery of edges of the cover together.

Referring now to FIG. 4, there are shown plan and side views of theinflatable support 10 illustrating the eight individual tubes 11, thelegs 12 and the platform 13 without any of the other equipment.

In FIG. 5, there is a plan view showing the opened pockets 16, the vents17, the pocket backing 16A, all of which secure the deployable cover(not shown). These pocket covers are held together by hook and loop tabs16B (of the type sold by Velcro) which are released during thedeployment of the cover.

In FIG. 6, there is a diagramatic sectional view showing a cylindricaltube 11 and a leg 12. The pocket backing is shown at 16A and the pocket,partially opened, is shown at 16. A portion of the cover 24 is shown asbeing fully deployed. As can be seen, the vent 17 is held above thewater line by the cylindrical tube 11. Thus, when the cover has beenfully deployed the air trapped under the cover can vent rapidly throughthe vent 17 so that the deployed device has a minimal protrusion abovethe water line.

Referring now to FIG. 7, there are shown schematic side and plan viewsof the firing system 14 illustrating a plurality of tubes 40 which areto hold the rockets, each tube having a firing mechanism 42 and a rockettriggering mechanism 44 mounted on the inner ends thereof. As noted fromFIG. 7, these tubes all project upwardly at a slight upward angle, onthe order of 12°, from a plate 46.

In FIG. 8, there is schematically shown a fire control mechanism whichis carried by the plate 46 which preferably supports the firing tubes40. This control system consists of an x-motion sensor 50, a y-motionsensor 52 and an accelerometer 56. The motions sensed by these devicesare fed to a power supply and control system 54. All of these arestandard, commercially available items, preferred embodiments of thedevices being described later in the specification.

In FIG. 9, there is shown a schematic diagramatic sectional view of agas cylinder 72 which serves as the gas rocket. This cylinder carries awasher 70 at its rear end, this washer being connected to a bridle 23which in turn is connected to the deployment lines 22 for deploying thecover 24 (see FIG. 2).

Referring now to FIG. 10, there is illustrated a detail of the gasrocket preferably employed in the present invention. This shows thelocation of a burst disk 75 which is to be ruptured by a cutter 76carried on the end of a firing mechanism 42 which is activated by anignitor 44.

As soon as an oil spill is encountered, the inflatable support isdeployed over the spill. Dispersal of the system can be accomplished bydropping it from the side of the ship 200 (see FIG. 3) or towing it awayfrom the side of the ship before deployment of the cover. Equally it canbe dispersed from another vessel or from an aircraft 300 (see FIG. 3).

Normally, the device will be confined in a canister 80 (See FIGS. 11 &12) which is adapted to fall away from the inflatable device when thecapacitor is in the water and the raft starts to inflate. The activationof the inflation system is accomplished by remote control and occurswhen the canister is in proper position.

As seen most clearly in FIG. 12, the raft 10 is stored in deflatedcondition in the canister 80 with all of the sections thereof inposition to be inflated. Inflation is accomplished by a gas control andbattery system 64. The anchor 30 is shown in the base 82 of thecanister. The two halves of the canister are held together by breakablestraps 83 which are too weak to resist the expansion force created bythe inflating raft.

Inflation of the raft effectively disengages the inflatable raft fromthe canister 80 and will prevent the support 10 from sinking. FIG. 13shows the raft partially inflated and being ejected from the lower half82 of the canister, this lower half not yet having sunk. The upper half81 has been discarded and is sinking. The lower half 82 is arranged tosink when the raft is fully inflated.

Once the raft has been fully inflated and is in position over an oilspill, a remote control device checks the circuits in the control systemto see that all circuits are functioning properly. At this point, thesystem for firing the gas propelled rockets is activated. This system ispreferably additionally controlled by the x and y sensors which checkfor pitch and roll of the platform 46. In addition, the accelerometer isread to make sure that the firing takes place at the top of a waverather than in the trough. As a result, when the platform 46 reaches thetop of a wave and is level, the eight rockets will be discharged byactivating the firing mechanism 44 and the puncturing mechanism 42 whichpropelles the cutter 76 through the burst disk 75. This releases the gaspressure which drives the rocket out of the tube 14, pulling the cords22 and deploying the cover 24 in its extended pattern.

At this point the raft 10, anchor 30 and inflation cylinder 62 are inthe general position shown in FIG. 14. The anchor is still retained by ayoke 61 which leads to a wire 65 supporting the anchor 30. On command aremote controlled cutter 60 severs wire 65 and releases the anchor. FIG.14 also shows the remote controlled gas release system for the inflationcylinder 62. As seen from FIG. 14, the lower case 82 has now sunk sothat the anchor is free to fall to the full depth allowed by anchor line32. If the lower case 82 has too much buoyancy, a controlled leak may beincluded in case 82 to provide a timed sinking. Equally, a valve timedto the inflation of the raft may permit flooding of case 82.

At this point the anchor release mechanism 60 is activated by remotecontrol and the anchor 30 is allowed to fall. The dropping of the anchor30 pulls on the lines 32 and draws the edges of the cover 24 downthrough the oil slick deep into the water to form the shape generallyshown in FIG. 3. This confines the oil in a central portion of the coverunderneath the raft 10.

During the operation of the deployment of the cover 24 and itscollection underneath the raft, air is rapidly released from under thecover through the vent 17 which, in the preferred embodiment, preferablycompletely surrounds the cylinder 11. Since the vent is held above thesurface of the oil and the water by the cylinder 11, oil cannot escapethrough this vent. After the oil has been collected, it can be retrievedfrom under the cover by a suitable pumping means which can be insertedunder the edge of the cover or can be pushed through an opening in aportion of the vent.

In a preferred embodiment of the invention, the cover 24 is preferably1.14 ounce rip stop nylon coated on one side in orange so as to beclearly visible. The cylinder, including the legs 12 and platform 13 aremade of 4.70 ounce neoprene with rip stop nylon covering. The platform46 is preferably a 30 inch circular flattened aluminum sheet 1/8th inchthick. The firing tubes are 2.610 inch ID×11 5/8 inch long extrudedaluminum tubes. The vent is preferably "texulene" 13 to 14 ounces, (aPVC Vinyl coated polyester 17×12 weave). The bridles are preferablyKevlar Aramid fibers 0.062 inch in diameter and the lines 22 arepreferably 5/16 inch braided nylon. The x and y sensors are preferablynormal sensors used in industry such as a Honeywell Microswitch No. 9SS.The accelerometer is a piezoelectric type available from SetraElectronics. The firing system 44, preferably is a Whittaker ordinance4406 thruster and the penetrating mechanism 42 is a stainless steel tubewith a sharp cutting edge 76 for penetrating the rupture disk 75. Asimilar system can be used for severing the anchor retaining wire 65.These Whittaker thrusters are completely contained and can be used in anexplosive atmosphere without danger. The rupture disk is preferably anAnsel 4526 rupture disk and the cylinder is preferably filled to apressure of 3000 psi. As a propellant compressed nitrogen is preferred.Such a filled cylinder weighs 4.6 lbs.

We claim:
 1. A system comprising a cover for being deployed over an oilspill for recovering oil entrapped by the cover, the improvement whereinthe cover is deployed by rockets secured around the periphery of thecover, each said rocket being propelled by a supply of high pressuregas, said cover being deployed from a floating support, and said systemalso comprises x and y sensors for detecting the attitude of saidsupport and means for controlling deployment of said cover as a functionof detected attitude, said x and y sensors and said controlling meansbeing located on said floating support.
 2. A system according to claim1, the improvement also wherein an inflated peripheral support has legsextending upwardly from the peripheral support, a platform carried bythe legs, and a pocket for holding said cover arranged around outer endsof the support legs, and an air vent in said cover adjacent saidperipheral support, the air vent being held above the level of trappedoil by means of said peripheral support, and permitting trapped air tobe removed therethrough.
 3. A system according to claim 1, wherein saidsupport comprises a canister for containing the cover and an inflatableraft for supporting the cover, said canister having at least twoseparable sections, said canister being sufficiently watertight toretain the canister afloat and in an upright orientation, said canistersections being releasable upon inflation of the support.
 4. The systemof claim 1 wherein each rocket comprises a high pressure supply of gasconfined by a rupturable disc and means are provided for rupturing saiddisc to fire the rocket.
 5. The system of claim 4 wherein the discrupturing means is impelled against the disc by an explosive device whenno explosive flames escape from the device.
 6. The system of claim 1wherein said system additionally includes a sensor for detectingvertical motion of said support.
 7. The system of claim 1 wherein saidsystem includes an air vent in said cover adjacent said peripheralsupport, the air vent being held above the level of trapped oil by meansof said peripheral support.
 8. The packaged system of claim 3 whereinsaid canister sections are arranged to sink after deployment of theinflatable raft.
 9. The system of claim 3 wherein said system includesan air vent in said cover adjacent said peripheral support, the air ventbeing held above the level of trapped oil by means of said peripheralsupport.
 10. The system of claim 9, wherein said vent is adapted topermit trapped air to be vented therethrough.
 11. The system of claim 1,wherein said system is adapted to be deployed over the spill bydispensing said system from an aircraft.
 12. The system of claim 1,wherein said system is adapted to be deployed from a water-borne vessel.13. A system according to claim 1, wherein said cover is contained in atleast one canister prior to deployment and said canister comprises atleast two sections held together by straps adapted to break upondeployment of said cover.
 14. A system according to claim 1, and furthercomprising, means for activating said rockets when said platform is atopa wave and is horizontally level.
 15. A system according to claim 9,wherein said air vent is adapted to permit insertion of pumping meanstherethrough whereby to permit removal of oil entrained by said cover.16. A system according to claim 1, wherein said high pressure gas isnon-flammable.